2.4 Ecological Tolerance

Ecological range

The range of conditions that an animal can endure before death

Examples of ecological range conditions

Temperature, salinity, PH, sunlight

Species and individual organisms both have a range of…

Tolerance for all the different environmental conditions of their habitats

What is good about having an ecological range?

It makes organisms more resistant to disturbances

Examples of ecological range

Salmon have a range of tolerance for temperatures between 6°-22°C but some salmon have a range that goes beyond that

Optimal range

The range where organisms survive, grow, and reproduce

Zone of physiological distress

Range where organisms survive, but experience some stress such as infertility, lack of growth, decreased activity etc

Zone of intolerance

Range where organisms will die

Ex. of zone of intolerance

Thermal shock, suffocation, lack of food/water/oxygen

How should you write FRQs about human activities or natural events that cause environmental disturbance?

You should connect your answer to ecological range of tolerance

How should you write a FRQ about about a shift in tolerance?

You should connect it to a specific kind of physiological stress

Examples of physiological stress

Suffocation, thermal shock, lack of water/food/nutrients/oxygen